(((LostinDC)))
I'm sorry that you're going through such a tough time.

Times like you're describing do stink!
Try to take this situation apart a bit, to gain better perspective. A less painful and less intense perspective.
1. You're upset with your T.
2. You're upset with yourself, for not achieving abilities that you think you should have.
3. You're disappointed with yourself.
Okay. Now out of the 3 above, what issue can be fixed most easily and quickly? Don't get me wrong either..I'm not saying that any are "easy". Just which issue is the
easiest for you to fix? 1, 2, or 3? I say this because we may very well have different opinions on what's an easier problem to fix.
#1) You can tell your T how hurt you are by your last appointment because of ______. Address the issue head-on, no *****-footing! Tell him that you're afraid of losing him, and having to start over with another T.
#2) Sooner or later in life, we ALL have to deal with some frustration in our lack of achievement/s. That is human. Sorry.

Reminding yourself of this could help you feel a little better sooner though.
#3) Self-disappointment is the most difficult issue for me to handle. I think that many of us hold ourselves to impossible standards, without much room for error ~ especially no room for tragedies that occur in life. Accepting that tragedies do occur, for lots of people (in many different ways), can help us feel less alone. But that doesn't mean that what happened to us wasn't tragic. It was (or is)! We just really need to adjust our expectations of ourselves to reasonable heights. Don't shoot super-low, but don't continue shooting super-high either.
That's my advice for the day. I hope that this helps you feel a little better. Best wishes to you!